What to send a 3PL for a quote, and why each file changes the price.

Send a 3PL three months of order history with the destination zip, SKU and quantity on every line, a SKU list with weights, packed dimensions and barcodes, your on-hand count, your returns, the channels you sell on, and the dates of your next sales and peaks. Each of those files sets a line on the quote. Whatever you leave out, the 3PL has to guess, and a guessed number tends to come back padded.

Below is the pack, file by file, with what each one changes in the price, how to pull the biggest one out of Shopify, and what to do when you don't have the history yet.

Why does a 3PL need your data to quote you?

Think of a quote as a model of your month. The warehouse takes what you tell it about orders, units, boxes and destinations, runs it through its rate card, and hands you a number. Say you send a one-line email that reads "about 2,000 orders a month, apparel". The model then runs on their idea of an apparel brand. That might be one T-shirt in a mailer. It might be six pieces in a carton. The rate card can't tell the difference, and neither can the person pricing it.

So the useful question isn't "what's your rate?" It's "what would my last three months have cost here?" You can only ask that if you hand over the last three months. It also makes quotes comparable, because every 3PL prices the same orders, and you can lay the totals side by side the way our guide to comparing 3PL quotes walks through.

The data pack, file by file

Here's what to put in the pack, what each file needs to contain, and which part of the price it moves. Keep it in one workbook with a tab per file, so nobody quotes from half of it.

You can leave out revenue and margin. What a 3PL prices is the units, boxes and labor hours behind each order, and none of that changes with what the order earns you, so keep the pack to physical facts.

How to pull three months of orders out of Shopify

The order history is the biggest file and the one that matters most, and in Shopify it's an export you already have. From the Orders page in the Shopify admin you click Export, choose orders by date with a start and end date, and Shopify emails the CSV to you and the store owner when the export is larger than a page (checked October 2026). The same page lists the columns a 3PL needs: Shipping Zip, Lineitem SKU, Lineitem quantity, Created at and Shipping Method, plus Tags.

1. 01Pick the three most recent full months. If none of them includes a sale or a holiday rush, add the month that did, and label it, so the 3PL sees your normal month and your busy one.
2. 02Export orders by date for that range as a CSV.
3. 03Keep these columns: Name (the order number), Created at, Shipping Zip, Shipping Country, Shipping Method, Lineitem SKU, Lineitem quantity, Tags. Delete customer names, emails, phone numbers and street addresses before you send it. The 3PL doesn't need them to quote, and you shouldn't hand them out.
4. 04Each order line is its own row, so an order with three SKUs takes three rows. Leave it that way. It's how the warehouse counts units per order.
5. 05If you sell on Amazon or TikTok Shop and fulfill those orders yourself, pull the same fields from each channel's order report and add a Channel column, so every order sits in one table.
6. 06Remove cancelled and unfulfilled test orders, and say in a note which filters you applied.

Your SKU list can come out of Shopify too. The product CSV carries a SKU column, a weight value in grams, a barcodes column, and packed product length, width and height columns with their unit (checked October 2026). If those packed dimension columns are empty in your export, fill them in from your packaging, measured with the product in it. That one afternoon of measuring is worth more to your quote than anything else on this list.

Why the weight and size of the box and the zip change the postage line

Postage is built from three things you control in the pack: what the parcel weighs, how big the box is, and where it's going. Leave any of them out and the 3PL estimates postage from a generic parcel.

Box size matters because carriers charge for space. For USPS Priority Mail, a parcel over one cubic foot, 1,728 cubic inches, is priced on its actual weight or its dimensional weight, whichever is greater, and for a rectangular box the dimensional weight is length times width times height in inches, divided by 139 and rounded up to the next pound (checked October 2026). Say you ship a 2 pound sweater in a 16 by 12 by 10 inch carton. That's 1,920 cubic inches, which divided by 139 is about 13.8, so Priority Mail rates it as a 14 pound parcel. A quote built on the sweater's weight alone would miss that by a long way.

Zips matter because carriers price by zone. On the USPS domestic zone chart you start from the zip you ship from, and the first three digits of the destination zip determine the zone (checked October 2026). A warehouse in New Jersey and one in California will price the same order to Brooklyn very differently, so a 3PL can only quote your postage if it can see where your customers are. Send the full destination zip on every order. A list of states isn't enough.

Packed dimensions also set your storage bill. They're what a warehouse uses to work out your cube, the cubic feet your stock fills on the shelf, which drives storage on a per cubic foot rate card. Our guide to storage fees shows how to turn carton sizes into that number.

The files people skip, like returns, channels and peak dates

Returns get skipped because nobody's proud of them. Send the count anyway. A brand with a lot of size exchanges needs grading time and bin space that a brand with almost no returns doesn't, and if the 3PL doesn't know, it either prices returns high to be safe or finds out after you've signed. Add your grading rule too: what counts as sellable, what gets set aside, whether you want refunds to go out when the parcel arrives. The returns process guide covers what that rule usually says.

Channels change what the warehouse has to connect to and which ship-by rules it has to meet. A Shopify order and a TikTok Shop order can be the same box, but the marketplace measures how fast it leaves, and a late one shows up on your seller account. If you send stock into Amazon's warehouses, that prep is its own line, so say how often you replenish and how many cartons a shipment usually is.

Peak dates decide whether there are people in the building when your orders land. Give the dates of every sale, drop and holiday push you've got planned for the next six months and the volume you expect from each. Then ask directly whether handling or storage rates change in those weeks, and get the answer into the quote.

What to send when you don't have three months of history

If you're launching, switching from shipping out of your garage, or opening a new channel, you won't have clean order history. Send what you do have and mark every estimate as an estimate. A 3PL can work with a forecast if it knows the shape: how many orders a month, how many units in a typical order, which SKUs sell most, and where your customers are likely to be.

• For order volume, use preorders, your waitlist, or the last launch, and give a low and a high month.
• For units per order, use your bundles and your honest guess at the typical basket. Say a typical order is one hoodie and one pair of socks. Write that down and the warehouse can price it.
• For destinations, use your email list or ad audience by state if that's all you have, and say so.
• For the SKU list, there's no shortcut. Every SKU needs a weight and packed dimensions before anyone can quote postage or storage honestly.

Ask the 3PL to list the assumptions it used, then check the quote again against your first real month. If you're shipping out of your own space today, our in-house versus 3PL comparison helps you work out what you're paying now, which is the number the quote has to beat.

The checklist before you hit send

• Three full months of order lines with destination zip, SKU, quantity, date and channel, and your busiest recent month if it isn't one of the three.
• Customer names, emails, phones and street addresses removed from every export.
• Every active SKU with a barcode, a unit weight, packed length, width and height, and units per master carton.
• On-hand units by SKU, with the slow sellers marked.
• How inventory arrives, how often, and whether it comes palletized, in cartons or floor-loaded.
• Returned parcels per month and your rule for what goes back on the shelf.
• Every channel you sell on and the share of orders from each, plus any Amazon inbound you'll want prepped.
• Sale, drop and holiday dates for the next six months, with expected volume.
• Packing rules per SKU, branded materials, inserts, and anything fragile, liquid, aerosol or alcohol-based.
• The same pack, sent on the same day, to every 3PL you're comparing.

How we turn your data pack into a quote at YNK

Our 3PL intake takes about ten minutes. It asks for your monthly orders, where you sell, your SKU count, what you sell, and your last three months of shipments, and we use the SKU list with sizes and weights, your packing and shipping rules and a rough inbound plan to model your profile. If you've already built the pack above, attach that to the intake instead.

We price it on our rate card, as estimates: $3.00 per order for handling, $0.65 per cubic foot per month for storage on the space you use, $3.00 per returned parcel, and $35 an hour for special projects like relabeling, only when you ask for one. Receiving is billed by the hour, packaging is billed as used, and there's no setup fee. Postage is billed semi-monthly per shipment, at extremely competitive carrier rates.

The baseline is one handling fee per order, however many units are in it, so your units per order matter less here than on a per-item rate card. A few order profiles are priced differently, and if yours is one of them the quote says so. We also go through your SKU list for aerosols and alcohol-based products before we quote, so the carrier and service are right from the first order. Someone from the team replies within one business day, and your proposal follows within five. The rate card works well for brands shipping 300 or more orders a month.